A5017162087- Iron-based superconductors research
- Physics of Superconductivity and Magnetism
- Rare-earth and actinide compounds
- Topological Materials and Phenomena
- Electronic and Structural Properties of Oxides
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Corporate Taxation and Avoidance
- 2D Materials and Applications
- Superconductivity in MgB2 and Alloys
- Inorganic Chemistry and Materials
- Advanced Chemical Physics Studies
- Quantum and electron transport phenomena
- Magnetic properties of thin films
- Intellectual Capital and Performance Analysis
- Organic and Molecular Conductors Research
- Chalcogenide Semiconductor Thin Films
- Heusler alloys: electronic and magnetic properties
- Graphene research and applications
- Surface and Thin Film Phenomena
- Semiconductor materials and devices
- Silicon Nanostructures and Photoluminescence
- X-ray Diffraction in Crystallography
- Superconducting Materials and Applications
- Nanowire Synthesis and Applications
National Synchrotron Radiation Laboratory
2022-2025
University of Science and Technology of China
2019-2025
State Key Laboratory of Surface Physics
2014-2024
Collaborative Innovation Center of Advanced Microstructures
2015-2024
Fudan University
2014-2024
Nanjing University
1994-2024
Hefei National Center for Physical Sciences at Nanoscale
2019-2022
ORCID
2021
Zhejiang University
2020
Institute of Modern Physics
2020
Kondo insulators (KIs) are strongly correlated materials in which the interactions between 4f and conduction electrons lead to a hybridization gap opening at low temperature 1-2. SmB6 is typical KI, but its resistivity does not diverge temperatures, was attributed some in-gap states 3-10. However after several decades of research, nature origin remain unclear. Recent band calculation transport measurements suggest that could actually be ascribed topological surface states. thus might first...
The dream of room temperature superconductors has inspired intense research effort to find routes for enhancing the superconducting transition (Tc). Therefore, single-layer FeSe on a SrTiO3 substrate, with its extraordinarily high Tc amongst all interfacial and iron based superconductors, is particularly interesting, but mechanism underlying remained mysterious. Here we show through isotope effects that electrons in couple oxygen phonons superconductivity enhanced linearly coupling strength...
Abstract Electron–electron and electron–phonon interactions are two major driving forces that stabilize various charge-ordered phases of matter. In layered compound 1T-TaS 2 , the intricate interplay between generates a Mott-insulating ground state with peculiar charge-density-wave (CDW) order. The delicate balance also makes it possible to use external perturbations create manipulate novel in this material. Here, we study mosaic CDW phase induced by voltage pulses, find new exhibits...
The Majorana fermion, which is its own anti-particle and obeys non-abelian statistics, plays a critical role in topological quantum computing. It can be realized as bound state at zero energy, called mode (MZM), the vortex core of superconductor, or ends nanowire when both superconductivity strong spin orbital coupling are present. A MZM detected zero-bias conductance peak (ZBCP) tunneling spectroscopy. However, practice, clean robust MZMs have not been vortices due to contamination from...
In a superconductor electrons form pairs and electric transport becomes dissipation-less at low temperatures. Recently discovered iron based superconductors have the highest superconducting transition temperature next to copper oxides. this article, we review material aspects physical properties of superconductors. We discuss dependence on crystal structure, interplay between antiferromagnetism superconductivity by examining neutron scattering experiments, electronic these compounds obtained...
The superconductivity of a kagome superconductor CsV_{3}Sb_{5} is studied by scanning tunneling microscopy and spectroscopy at ultralow temperature with high resolution. Two kinds superconducting gaps multiple sets coherent peaks residual zero-energy density states (DOS) are observed on both half-Cs Sb surfaces, implying multiband superconductivity. In addition, in-gap can be induced magnetic impurities but not nonmagnetic impurities, suggesting sign-preserving or s-wave order parameter....
High-temperature superconductivity was discovered in the pressurized nickelate La3Ni2O7 which has a unique bilayer structure and mixed valence state of nickel. The properties at ambient pressure contain crucial information fundamental interactions bosons mediating superconducting pairing. Here, using X-ray absorption spectroscopy resonant inelastic scattering, we identified that Ni 3 $${d}_{{x}^{2}-{y}^{2}}$$ , $${d}_{{z}^{2}}$$ ligand oxygen 2p orbitals dominate low-energy physics with...
Altermagnetism (AM), a newly discovered magnetic state, ingeniously integrates the properties of ferromagnetism and antiferromagnetism, representing significant breakthrough in field materials. Despite experimental verification some typical AM materials, such as MnTe MnTe_{2}, pursuit materials that feature larger spin splitting higher transition temperature is still essential. Here, our research focuses on CrSb, which possesses Néel up to 700 K giant near Fermi level (E_{F}). Utilizing...
FeSe layer-based superconductors exhibit exotic and distinctive properties. The undoped shows nematicity superconductivity, while the heavily electron-doped KxFe2-ySe2 single-layer FeSe/SrTiO3 possess high superconducting transition temperatures that pose theoretical challenges. However, a comprehensive study on doping dependence of an superconductor is still lacking due to lack clean means control. Through angle-resolved photoemission spectroscopy studies K-dosed thick films FeSe0.93S0.07...
Sr2IrO4 was predicted to be a high temperature superconductor upon electron doping since it highly resembles the cuprates in crystal structure, electronic structure and magnetic coupling constants. Here we report scanning tunneling microscopy/spectroscopy (STM/STS) study of with surface by depositing potassium (K) atoms. At 0.5-0.7 monolayer (ML) K coverage, observed sharp, V-shaped gap about 95% loss density state (DOS) at EFand visible coherence peaks. The magnitude is 25-30 meV for...
While the parent compounds of cuprate high temperature superconductors (high-Tc's) are Mott insulators, iron-pnictide high-Tc's in vicinity a metallic spin density wave (SDW) state, which highlights difference between these two families. However, insulating were identified for newly discovered KxFe2-ySe2. This raises an intriguing question as to whether iron-based could be viewed doped insulators like cuprates. Here we report angle-resolved photoemission spectroscopy (ARPES) evidence and one...
Single-layer FeSe films with extremely expanded in-plane lattice constant of 3.99A are fabricated by epitaxially growing FeSe/Nb:SrTiO3/KTaO3 heterostructures, and studied in situ angle-resolved photoemission spectroscopy. Two elliptical electron pockets at the Brillion zone corner resolved negligible hybridization between them, indicating symmetry low energy electronic structure remains intact as a free-standing single-layer FeSe, although it is on substrate. The superconducting gap closes...
To understand the pairing symmetry and superconducting transition temperature in heavily electron-doped iron-based superconductors, it is important to study more of these materials, especially ones with decent stability air without phase separation. Here, angle-resolved photoemission spectroscopy probes surface electronic structure gap new superconductor (Li${}_{0.8}$Fe${}_{0.2}$)OHFeSe, which shows a ${T}_{c}$ as high 40 K.
Heavy-fermion systems share some of the strange metal phenomenology seen in other unconventional superconductors, providing a unique opportunity to set metals broader context. Central understanding heavy-fermion is interplay localization and itinerancy. These materials acquire high electronic masses concomitant Fermi volume increase as $f$ electrons delocalize at low temperatures. However, despite wide-spread acceptance this view, direct microscopic verification has been lacking. Here we...
Quantum critical behavior occurs at low temperatures where quantum fluctuations become more important than thermal fluctuations. Of particular current interest is unconventional criticality, which lacks a classical counterpart. Angle resolved photoemission and scanning tunneling microscopy are experimental techniques that measure single-particle excitations, recently been used to probe strongly correlated metals near points Here, how the properties reflect criticality discussed, prospect for...
Extremely high magnetoresistance (XMR) in the lanthanum monopnictides $\mathrm{La}X$ ($X\phantom{\rule{0.28em}{0ex}}=\phantom{\rule{0.28em}{0ex}}\mathrm{Sb},\phantom{\rule{0.28em}{0ex}}\mathrm{Bi}$) has recently attracted interest these compounds as candidate topological materials. However, their perfect electron-hole compensation provides an alternative explanation, so possible role of surface states requires verification through direct observation. Our angle-resolved photoemission...
The authors demonstrate experimentally the existence of theoretically predicted antiferromagnetic Dirac states in kagome compound FeSn, where $P$ and $T$ symmetries are individually broken but combined $P\phantom{\rule{0}{0ex}}T$ symmetry is present. Moreover, their theoretical analysis reveals that, due to salient structure, fermions can be transformed into either massless/massive Weyl or massive via manipulation, study does report experimental observation Weyl-like cones at surface driven...
ABSTRACT Superconducting infinite-layer (IL) nickelates offer a new platform for investigating the long-standing problem of high-temperature superconductivity. Many models were proposed to understand superconducting mechanism based on calculated electronic structure, and multiple Fermi surfaces orbitals involved create complications controversial conclusions. Over past five years, lack direct measurements structure has hindered understanding nickelate superconductors. Here we fill this gap...